Caractérisation chimique et transformation synthétique et hémisynthétique des composés volatils de trois espèces de la famille des Apiaceaes : Smyrni.um olusatrum, Daucus crinitus et Eryngium triquetrum

Abstract

The main objective of this thesis is a better knowledge and a valuation of the flora richness of the Algerian West which remains, to this day, largely unknown. This work constitutes an initiation to investment projects in the field of PPAM on the basis of scientific results developed in laboratories specializing in the chemical and biological valuation of essential oils. Thus, the study concerns a chemical characterization and an evaluation of the biological activities of the secondary metabolites of the volatile fraction of three species of Apiaceae (family of Umbellifera) (E. triquetrum, S. olusatrum, D. crinitus) growing in the spontaneous state in western Algeria and the synthesis of the majority compounds of these volatile fractions As described in the title, the purpose is therefore the search for new extractables, i.e. new molecules likely to be active vis against pathologies, parasites or even agricultural pests. The use of chromatographic techniques (CPG-DIF, CPG-MS, Flash chromatography) allowed a better knowledge of the essential oils of the species studied. They have provided important information on the chemical composition of volatile constituents of the plant during the vegetative cycle and depending on its geographical location. Thus a good separation of the dominant compounds in essential oils.These essential oils are rich in compounds with very interesting therapeutic properties. This work was also an opportunity to carry out structural investigations (MS. 1D NMR) which led to the identification of the synthesized molecule called “isochavicol isobutyrate” which is the major compound of the essential oil of D. crinitus aerial part. These volatile matrices were the subject of a biological evaluation which showed a certain reactivity towards the different agents tested. In particular, the essential oils tested showed antimicrobial activity against Enterococcus faecalis and Staphylococcus aureus, as well as interesting bioherbicidal, insecticidal and molluscicidal activities. These essential oils can be biocontrol agents that replace synthetic products against agricultural pests. The oil of E. triquetrum has a molluscicidal power against the parasites it has an effective and selective behavior vis-à-vis the schistosoma